RE: the burton fish, I am under the impression you typically downsize when you ride a true powder board, and being 155lbs a 160 fish seems a tad large. If you were grabbing a standard board, then upsizing would be the move.
If anyone can confirm or correct me that would be great.

I had to google "a true powder board" because I think a lot of peoples interpretation of a true powder board differ. Back in the day, that just meant huge but not any more.